As already known, a silicon wafer used to manufacture a semiconductor device is produced as follows. A rod-like polycrystalline silicon lump is first produced by the Siemens method and then crushed into fist-sized small pieces. Then, a columnar silicon ingot is produced from the obtained small silicon pieces as raw materials by the Czochralski method, sliced and ground to obtain the silicon wafer.
Patent Document 1 listed below discloses a silicon lump crushing tool which can be used to crush a silicon lump into small silicon pieces. This silicon lump crushing tool comprises pneumatic drive means for driving a piston which is installed in a casing in such a manner that it can move between a retreat position and a projection position and is driven from the retreat position to the projection position by the action of compressed air, a guide tube connected to the casing and extending in the moving direction of the piston, and a hammer head whose rear end is movably inserted into the guide tube. To crush a silicon lump, the piston is driven from the retreat position to the projection position by the action of compressed air while the end of the hammer head is in contact with the silicon lump. Then, the end of the piston collides with the rear end of the hammer head, whereby an impact is applied to the hammer head and transmitted to the silicon lump to crush it.
Patent Document 2 listed below discloses a silicon lump crushing apparatus for crushing a silicon lump by pinching a polycrystalline silicon rod between a pair of pressing/crushing members and pressing it.